1.2 Included in this guide are the recommendations for determining the number of significant figures for specifying chemical composition.

1.3 The carbon and alloy steel grades in all standards overseen by the aforementioned ASTM subcommittees have been included, except those grades applicable to restricted special end uses.

1.4 Not addressed are minor composition modifications that a specific ASTM subcommittee may find necessary to accommodate effects of normal processing or to enhance fabricability by the producer or user, or both.

1.5 Also not generally addressed (except where established by ASTM subcommittees) is a complete rationalization of all limits, especially where such would conflict with long-standing practices and is not justified by special technical effect.

1.6 This guide does not address discontinued or formerly standard steel grades. A listing of such steel grades can be found in SAE J1249. Also excluded from this guide are cast materials and welding filler metals.